1988 Mazda B2200 2.2L carburated from North America

Summary:

Faults:

On cold days here in Canada, the choke picks the odd day that it wants to work, other days it just makes the engine hesitate. The truck only gets 15 mpg because no one can tune the electronic carburettor on this thing. Smokes heavily on startup, then quits when warm even though the head is new and compression is 165 lbs.

Rear differential is now making a noise and vibrating the truck.... will likely go next!

General Comments:

This appears to be a vehicle very sensitive to how it was maintained. Not knowing how it was taken care of previously, it could likely be the problem. I work with a guy who has 400,000 km on one and he swears by it. I will not buy another one.

I would go back to a Toyota in a heart beat if I could justify the over-inflated prices!

1st Feb 2001, 22:28

21st Feb 2001, 12:25

I am also from Canada (i.e. Mississauga), and have the same vehicle; it has shown symptoms similar to yours. I thought that the choke was stuck on cold days, which caused the engine to rev high and waste gas - even with the engine fully-warmed. Yesterday, I discovered that the problem was not the choke at all - it was the EGR valve!

The EGR valve is a pollution-control device. Its job is to reduce NOx emissions by keeping the temperature of the combustion chamber at just below 1371 degrees C (2500 F). It does so by recirculating a small percentage of the exhaust gas back into the engine (i.e. less than 10%); it has an effect similar to spraying your backyard barbeque with a small amount of water when it flares-up.

On a Mazda B2200, according to the owner's manual, the EGR valve should be replaced every 96 000 km. It is quite simple to replace yourself; this process should take no more than 10 minutes of your time, although the dealer would charge for one flat-rate hour of labour. However, this part is not cheap. According to the Mazda price list, a new EGR valve for this vehicle is CD$228.57 + applicable taxes; the aluminum gasket that goes with it is another $2.53 (you should always order one when replacing it). The procedure for replacing it is as follows:

1. Make sure that the engine is off before proceeding.

2. Locate the old EGR valve; it is located under the hood on the passenger side under the air cleaner assembly (You do not need to remove this assembly to find it! Look to the left side of the engine block.). It is mounted to the engine block over the gasket, and is secured with three bolts.

3. Disconnect the vacuum line that connects to the EGR valve.

4. Loosen each of the bolts, and it should come right off. Remember the orientation of the gasket before taking the bolts out.

5. Unplug the EGR valve.

6. Mount the new EGR valve over the new gasket, making sure the gasket is in the correct orientation. Do not overtighten the bolts.